Although in the case of Dr Geza De Kaplany where he had used acid as a means of killing his wife Hajna De Kaplany this was perhaps the exception. She was an attractive girl who was a model and just 20 years old when she was murdered by her husband on 28th August 1962. It is hard to imagine a more painful way to die than to be covered in acid. She was suffering from third degree corrosive burns and lingered in hospital for 36 days before dying.
A very prominent case in which the murderer hoped to avoid detection by disposing of the body in acid is of course that of John George Haigh who on the 18th February 1949 drove to Haigh's ramshackle workshop in Crawley in his Alvis to discuss a business venture. Here he shot her in the back of the head and, after removing her jewellery and fur coat, put her body in a 45-gallon corrosion resistive drum and filled up the tank with sulphuric acid.
The next day, Saturday, guests at the hotel, who were getting anxious about the absence of Mrs Durand-Deacon from breakfast, asked Haigh if he knew of her whereabouts. He told them that he had arranged to meet her but that she had failed to turn up for their appointment. By the Sunday, it was obvious that something was wrong.
On Monday, Scotland Yard's Record Office was contacted and Haigh's criminal record came to light. Haigh had driven to Crawley that morning and emptied the sludge from the tank onto the ground outside the workshop. He had then gone to Horsham and had Mrs Durand-Deacon's jewellery valued. When he returned to the hotel the police were waiting for him. He gave them a statement re-iterating his story about the missed appointment.
Thursday saw the police back at Onslow Court Hotel for another statement from Haigh, which was largely the same as his first statement but with a few extra details. Saturday 26th February and the police visited the workshop at Crawley. The door to the workshop was forced and the detectives noted the rubber apron, gas mask and empty carboys. They also found a recently fired .38 Enfield revolver and a dry-cleaning receipt for a black Persian lamb coat.
At 4.15pm on Monday 28th February, Detective Inspector Albert Webb was waiting at Onslow Court when Haigh returned. Webb took Haigh back to Chelsea police station to 'assist them with their enquiries.' Later that night he confessed to Webb saying, 'I've destroyed her with acid. You'll find the sludge that remains at Leopold Road. Every trace has gone. How can you prove murder if there's no body?' He went on to add the McSwanns and the Hendersons to his confession, claiming that he had killed them all so that he could drink their blood.
On Tuesday 1st March, Home Office pathologist, Dr Keith Simpson examined the Crawley workshop. He found bloodstains on the walls and a hat-pin at the bottom of the 45-gallon drum. After Dr Simpson had noticed a gall stone in the sludge in the yard all the residue was collected and taken to the police laboratory. Here it was processed and it produced a list that included 28lb of animal fat, part of a foot, two more gall stones and a full set of dentures. These, once identified by Mrs Durand-Deacon's dentist, sealed Haigh's fate. Even acid has its limitations.